SmartPendant

Firmware for the SmartPendant for grblHAL project.

Software

To clone the project:

git clone --recurse-submodules https://github.com/nickshl/SmartPendant.git

Building using the IDE

You can import the project into STM32CubeIDE.

You can then download the firmware with STM32CubeProg.

Building from the command line

Prerequisites:

• gcc C/C++ compiler (arm-none-eabi-gcc)
• CMake (version 4.0.0 or newer)

Run CMake:

mkdir build
cd build
cmake -DCMAKE_TOOLCHAIN_FILE=./cmake/arm_none_eabi_gcc.cmake -DCMAKE_BUILD_TYPE=Debug ..

Now you can build the project using make.

Hardware

Fully assembled custom board is available here (US only): https://devtronic.square.site/

To make this project yourself, you will need three essential parts:

• WeAct BlackPill F411 25M HSE:

• 3.5" Display with touchscreen based on ILI9488 LCD controller and FT6236 touch controller

• 60 mm 6 pin 100 PPR handwheel

This handwheel also works with 3.3V. The STM321F411 pins that the handwheel is connected to are 5V tolerant, so it can be powered from 5V. Note that pendant itself needs 5v power supply, it won't work with 3v.

• 3D printed Case

Compatibility

• Controller running latest GrblHAL

• Available UART port

• Controller's UART port should be configured in "MPG & DRO mode"

Detailed instructions how to check compatibility are available here.

GRBLHAL Configuration recommendations

Consider turning on these options inside GRBLHAL General section:

• Work coordinate offset

• Overrides

• Enable when homing

Debugging

You can uncomment #define SEND_DATA_TO_USB line in Application/GrblComm.h file, recompile firmware. With that controller mirrors all GRBL communication protocol to USB-based com port.

Probing

Center Finder

You can select which axes will be used for searching. Active axes are highlighted in red. For outside center finding 2 additional parameters are available: DISTANCE - how far to travel before lowering probe. CLEARANCE - lowering depth.

Edge Finder

Active axes are highlighted in red. You can also select which direction to travel using + and - fields. At the end of the process probe will be positioned at the very edge. CLEARANCE controls how far probe will be raised after the process.

PRECISE button allows performing 2 consequent measurements by rotating probe 180 deg after the first measurement for improved precision.

Tool Offset

After using first tool, jog over probe and click measure base before changing. Change to the next tool and click measure offset. After process is completed, new tool offset will be set to match first tool length.

Schematic

Schematic vesion 1.3(and later versions, only layout slightly changed):

Precompiled Firmware

Latest firmware HEX file can be found in Release folder: SmartPendant.hex

To load new firmware STM32CubeProgrammer is used:

1. If your device programmed with version 0.027.0 or later, hold top edge (MPG) button. Otherwise (not programmed, update failure, older version) hold BOOT0 button on the back instead.
2. Connect SmartPendant to PC using USB-C cable (it should be powered only from the USB!) or hit reset button on the back if it already connected and powered.
3. Couple seconds later release MPG or BOOT0 button.
4. Open STM32CubeProgrammer. In top right corner choose "USB" from drop down list.
5. If field "Port" in "USB Configuration" show "No DFU detected" click update button near it.
6. Click "Connect" button - STM32CubeProgrammer should establish connection and show current device memory content.
7. Click "Open File" in left to corner, select firmware HEX file, then click "Download" button in top left corner.
8. When flashing is done, close STM32CubeProgrammer and power cycle the device or short press NRST button on the device to restart it.

Note: If during update you get an error, you may try to use a different cable, another PC, connect device to the PC via USB hub (that usually helps for some reason) or slightly heat up STM32F411 MCU with a hair dryer. This error appears because STM32 bootloader uses internal RC oscillator to measure crystal oscillator frequency. According to Application Note AN2606, external crystal oscillator can be in range 4...26 MHz with 1 MHz step. However higher frequencies have lower error margin which in some cases can cause incorrect frequency detection and errors during bootload process.

Not relevant anymore: if flashing is successful, but firmware isn't work, check STM32CubeProgrammer log. If it says "sector 0000 does not exist" erasing operation wasn't successful and new firmware "merged"(write operation can only flip bits from 1 to 0) with old one. To fix this issue, press "eraser" button in bottom right corner and click "Ok" button in pop up window. After erasing is finished "Device memory" should show only FFFFFFFF. Flash new firmware after that.

Starting from version 0.027.0 if firmware detects that top edge (MPG or KEY on BlackPill) button is pressed, it calibrates internal RC oscillator and makes jump to bootloader, which should mitigate problem described above.

Thanks

Many thanks to Terje who made this project possible by adding another datastream to grblHAL.